The present invention relates generally to wireless communications devices, and more particularly to image exchange in wireless communications devices capable of push-to-talk service.
Push to talk (PTT) service is a half-duplex voice service wherein mobile terminals operate similarly to a walkie-talkie. Only one user speaks at a time while all other users listen. To talk, a participant presses a PTT button and begins speaking while holding the PTT switch. A participant releases the PTT switch when he/she is finished speaking to give other participants a chance to speak. PTT services may be provided over packet-switched wireless networks. Such services are commonly known as PTT over cellular, which is abbreviated PoC. PoC uses the Session Initiation Protocol (SIP) for establishing modifying and terminating sessions. PoC enables group conferences between two or more participants.
Two important aspects of PoC services are floor control and presence services. Floor control is a method of controlling access to a shared resource. Access to the shared resource may be exclusive or non-exclusive. In the context of group PTT conferences, floor control refers to a method of controlling access to the shared communication channel by users, which is typically exclusive. Temporary permission to access the shared communication channel, referred to as the floor, is granted to PoC clients by a floor control server. The floor control server manages the floor and provides notifications to users clients to indicate who currently has control of the floor.
Presence services provide information about the availability and status of users. A presence server maintains the presence status of users (e.g. “reachable,” “do not disturb,” “unavailable,” “offline,” etc.), and supports publication of presence information to users. With presence services, a user can make “buddy lists” and check the availability and status of other users.
Mobile terminals with PTT capabilities currently employ a rudimentary interface comprising a list of users in text format and simple icons or graphics to indicate control of the floor and the presence status of users. A more visually-oriented interface would be more appealing to end users, would enhance the overall user experience, and would help in attracting more subscribers to PTT services.